Preventing global surface air temperatures from rising too high will require emissions to be reduced and CO2 to be removed (captured) from the air. Many ways to do this have been proposed, although none to date are both technologically and economically feasible, so new and better strategies are needed. Rau et al. suggest that generating H2 with a combination of saline water electrolysis and mineral weathering, powered by electricity not derived from fossil fuels, could greatly increase energy generation and CO2 removal, at a lower cost than methods involving biomass energy plus carbon capture and storage. This approach also would allow carbon to be sequestered as long-lived ocean alkalinity rather than as concentrated CO2.